1. Field of the Invention
The present invention relates to a heat sink, and more particularly to a heat sink having components with minimal resistance to forced airflow.
2. Related Art
In contemporary computers, the most common kind of heat-generating electronic device is a Central Processing Unit (CPU). The CPU is the most important controller of electronic signals in a typical computer. A great deal of heat is generated by contemporary CPUs during normal operation. This can deteriorate the stability and operation of the CPU. Thus heat must be removed from the CPU quickly, to ensure proper operation of the computer. Oftentimes, a heat sink is mounted on a top surface of the CPU to remove heat therefrom.
A conventional heat sink includes a base positioned in contact with a CPU, and a plurality of fins radially extending from a center of the base. A rotary heat sink fan is frequently attached to a top of the heat sink, for providing forced airflow and facilitating heat convection.
Blades of the fan revolve and create centrifugal outgoing airflow. The directions of such airflow correspond to the orientation of the blades. When such air enters a conventional heat sink, it strikes the radial fins, rebounds, and also creates obstructing airflow. Additionally, part of the air emitted by the fan strikes a top surface of the base, rebounds back toward the fan, and creates obstructing airflow. All this retards air from entering the heat sink and exiting the heat sink, and thus reduces the efficiency of forced convection.
Examples of conventional heat sinks are disclosed in U.S. Pat. No. 5,794,685 and in Taiwan Patent Application No. 84310595.
Accordingly, an object of the present invention is to provide a heat sink which minimizes resistance to incoming forced airflow and outgoing airflow, and thus enhances heat convection.
To achieve the above object, a heat sink comprises a circular base, a plurality of fins and a central post. The base is adapted to be in thermal contact with an electronic device, to remove heat therefrom. The post extends from a top surface of the base. The post has a first surface connected to the top surface and a second surface dimensioned according to a rotary heat sink fan to be attached thereon, to minimize blockage of cooling air emitted from the fan. The post also has a concave side surface connected between the second surface of the post and the top surface of the base, for directing airflow toward an exterior of the heat sink and minimizing resistance to incoming airflow. The fins are identical in height to the post, so that cooling air emitted by the fan passes directly into the heat sink. The fins are curved, aligned and spaced from each other at uniform intervals corresponding to directions of airflow generated from the fan. This minimizes resistance to cooling air entering and exiting the heat sink.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed embodiments of the present invention with attached drawings, in which: